Chemical Reaction Test 2

Based on molecular structure and intermolecular forces, substance C would be predicted to have the greatest viscosity. This is because substances with larger and more complex molecules tend to have stronger intermolecular forces, which in turn leads to higher viscosity. Additionally, substances with higher molecular weight also tend to have higher viscosity. Therefore, substance C, which likely has larger and more complex molecules compared to the other substances, would be expected to have the greatest viscosity.

When the valve is opened and the gases mix, the total pressure in the container will be the sum of the partial pressures of neon and helium. Since the volume of the left hand bulb is larger than the right hand bulb, the neon gas will occupy a greater volume and therefore contribute more to the total pressure. As a result, the partial pressure of neon will be greater than the partial pressure of helium. The ratio between the partial pressures can be calculated by dividing the volume of the left hand bulb by the volume of the right hand bulb, which gives a ratio of 3:1. Therefore, the partial pressure of neon is 1.50 times as great as the partial pressure of helium.

The concentration of a solution is defined as the amount of solute (in this case, NaCl) dissolved in a given volume of solvent (in this case, water). If the concentration of the solution increases after several days, it means that the amount of solute has remained the same while the volume of solvent has decreased. Therefore, the increase in concentration can be attributed to the evaporation of water from the solution. Since the concentration increased by 0.33 M, it means that 0.33 moles of NaCl are dissolved in the remaining volume of water. Using the equation C1V1 = C2V2, where C1 is the initial concentration, V1 is the initial volume, C2 is the final concentration, and V2 is the final volume, we can calculate the volume of water that evaporated to be 20.0 mL.

The correct answer is D because it shows the formation of solid lead iodide (PbI2) as a product of the reaction between lead (II) nitrate and potassium iodide. In the reaction, the lead (II) cations from lead (II) nitrate combine with the iodide anions from potassium iodide to form solid lead iodide. This is represented in option D, where the lead (II) cations are shown bonded with the iodide anions to form the solid product. Options A, B, and C do not accurately represent the formation of lead iodide as a product.

Based on periodicity and intermolecular forces, the boiling point of a compound depends on the strength of the intermolecular forces between its molecules. The strength of these forces is determined by the polarity of the molecule and the size of its atoms. In this case, hydrogen fluoride (HF) and hydrogen iodide (HI) would have higher boiling points than hydrogen bromide (HBr) because they have stronger intermolecular forces. HF is a polar molecule and can form strong hydrogen bonds, while HI is a larger molecule with stronger London dispersion forces. Therefore, the correct answer is HI and HF.

Real gases deviate from ideal gas behavior at high pressures and low temperatures. In real gases, the gas particles have volume and experience intermolecular forces, unlike in ideal gases where the particles are assumed to have no volume and no intermolecular forces. Due to these factors, the observed pressure of a real gas will be less than the ideal pressure because the gas particles occupy space and exert a repulsive force on each other. Additionally, the volume available for the gas particles will be less than the volume of the container because the gas particles occupy space themselves.